Ignition apparatus



June 2, 1942. J. BOHLl 2,285,107

IGNITION APPARATUS Filed March 24, 1939 2 Sheets-Sheet 1 I N VENT OR.

ATTORNEY.

June 2, 1942. J. BOHLI iGNITION APPARATUS Filed March 24, 1939 2 Sheets-Sheet 2 FIG-2 QJVENTOR. jww M FIG. 3

Patented June 2, 1942 IGNITION APPARATUS Jakob Bohli, Solothurn,

Bendix Aviation Corporation,

Switzerland, assignor to South Bend, Ind.,

a corporation of Delaware Application In 14 Claims.

This invention relates to ignition apparatus and more particularly to internal combustion engine ignition systems and current generating and distributing means therefor.

One of the objects of the present invention is to provide a novel ignition system adapted for use in internal combustion engines or the like.

Another object of the invention is to provide novel ignition apparatus adapted for use in the ignition systems of multiple ignition engines.

Still another object is to provide a novelly combined distributor and magneto-generator for the ignition system of an internal combustion engine or the like.

A further object is to provide novel means for supplying current to a plurality of ignition circuits, each having a plurality of series connected induction coils therein.

A still further object is to provide a unitary magneto-generator unit for supplying current to a plurality of ignition circuits, each having an interrupter, a condenser and distributor means.

Still another object is to provide multiple ignition magneto-electric apparatus wherein a magnetic rotor, distributor and interrupter cams are concentrically mounted.

Another object is to provide novel apparatus in a multiple ignition system for internal combustion engines whereby accurate and individual timing of the sparks, as well as group timing thereof, may be readily effected.

Another object is to provide a novel magnetogenerator and distributor unit for multiple ignition engines which is so constructed that it is extremely compact and symmetrical.

The above and further objects and novel features of the invention will more fully appear from the following detailed description when the same is read in connection with the accompanying drawings. It is to be expressly understood, however, that the drawings are for the purpose of illustration only and are not intended as a definition oi the limits of the invention, reference being primarily had for this latter purpose to the appended claims.

In the drawings wherein like reference characters refer to like parts throughout the several views,

Fig. 1 is a side elevation, partly in section and with parts broken away, illustrating one form of the novel magneto-generator and distributor unit comprehended by the present invention;

Fig. 2 is a section along line II-II of Fig. 1;

Fig. 3 is a sectional view along line III-III March 24, 1939, Serial No. 264,002 Switzerland April 1, 1938 of Fig. 1 showing the top of the magnetic rotor;

Fig. 4 is a diagrammatic view of a portion of a novel ignition system in which the apparatus of Fig. 1 may be employed.

In the single embodiment of the invention illustrated in the drawings, by way of example, a triple ignition system is shown, but it will be understood that the novel apparatus disclosed may be adapted for use in other types of systems, such as for dual ignition. Each ignition circuit, in the illustrated system is equipped with two induction coils connected in series, an interrupter and distributor means thus rendering it possible to vary the timing of the spark or discharge in each individual circuit, as well as the timing of the groups of sparks in the several cylinders of a multiple cylinder engine.

The novel magneto-generator and distributor unit comprehended bthe invention is preferably housed in a metallic casing I having a metallic cover Ia for radio shielding purposes. The general construction of the stator and rotor elements of the generator is substantially the same as that illustrated and described in my copending application Serial Number 142,061, filed May 11, 1937, for Magneto-electric ignition apparatus.

Briefly, the stator of the illustrated unit comprises a pair of non-magnetic plates 25 and 26 supported on internal shoulders in casing I, said plates in turn supporting a plurality of equallyspaced, circularly-arranged induction coils, each consisting of a laminated core 5, a secondary winding 6 and-a primary winding 1. The upper ends of cores 5, as viewed in the drawings, extend into an annular groove in plate 25 and are magnetically connected by arcuate laminated bars 21 (Fig. 3) of magnetic material, such as soft iron. The lower ends of said cores extend through plate 26 into inductive relation with a magnetic rotor 4. The latter is fixedly mounted on a rotatable shaft 2 which may be supported by any suitable means, such as ball bearings centrally disposed in plates 25 and 26.

Rotor l, in the form shown, comprises a disc 28 of non-magnetic material that is provided with an annular groove in which a plurality of permanent magnets 3 are circumferentially spaced with like poles of successive magnets adjacent and magnetically connected by arcuate laminated bars 29 of magnetic material, such as soft iron. Thus, during the rotation of the rotor, when magnets 3 reach positions between the lower ends of cores 5, magnetic flux will flow from the adjacent, north poles, for example, of

two of the magnets to the center oi the intermediate bar 29, across air gap 30 and into one of the coil cores 5. At the upper ned of said core the flux divides and flows in opposite directions through bars 21 and thence downwardly through the cores of adjacent coils, across air gap 30 into bars 29 of rotor 4 and back to the south poles of the magnets from whence the flux originated. At any particular instant, therefore, magnetic flux flows upwardly through three alternate cores 5 and downwardly through the other three. After each rotation of the rotor through of a revolution, the magnetic flux will flowithrough each of the cores or bars 5 in the opposite direction. In the embodiment shown, therefore, six reversals of flux will occur in each of the coils 6, 1 during each revolution of shaft 2 and rotor 4.

For the purpose of adapting the above-described magnets to a multiple ignition engine, such as one employing triple ignition, for example, coils 6, l are connected together and in circuit with an interrupter and distributor means in a novel manner. In the form illustrated coils 6, 1 are connected in pairs with the primary windings l and the secondary windings 6, respectively, of each of the three pairs connected in series, as shown in Fig. 4, i. e., the primary windings of each pair of coils are connected in series with each other and the secondary windings of each pair of coils are connected in series with each other. Each pair of series connected primary windings 1 are connected to ground and in circuit with a suitable circuit breaker to be hereafter described. A condenser I2 is also connected across each pair of the primary windings. Each pair of secondary windings 6 is connected through a novel distributor, described hereinafter, to an ignition device, such as the center electrode of a spark plug 3| (Fig. 4). Three spark plugs, each connected in an independent circuit, may thus be provided in each cylinder of a multicylinder engine for producing three simultaneous or nearly simultaneous sparks.

The means provided in the illustrated embodiment for making and breaking the circuits comprising primary windings l, to thus induce a high tension current in secondary windings 6, comprises three circuit breakers 8, 9 and I0, one for each pair of series connected coils 6 and l. The breakers may be of any of the many types wellknown in the art and may be mounted in any suitable manner for individual timing adjustment in a recess formed in the top of a distributor block II of insulating material which is supported by plate 25 in the upper end of casing I. Since adjustable circuit breakers are wellknown in the art it is believed to be unnecessary to illustrate and describe the same in more detail. The circuit breakers shown are adapted to be operated by three suitably shaped earns 32 in a manner well understood in the art, said cams being axially disposed on the upper end of shaft 2. Condensers l2 may also be mounted in the recess in distributor block H beside the interrupter means.

In order to conduct and distribute the high tension current induced in the several pairs of secondary windings 6 to spark plugs 3| for igniting explosive charges in a plurality of engine cylinders in the desired sequence there is provided a novel distributor, the rotating element 13 of which is mounted on shaft 2 between interrupter cams 32 and plate 25. In the present embodiment, rotor element l3 has three contacts containing at least two tacts or terminals 20, 2i

extending axially therethrough and disposed at different radial distances from the axis of rot-ation. The lower ends of said rotor-contacts are adapted to cooperate with rows of contacts or rings I1, l8 and I9, respectively, which are also arranged in concentric circles of different diameters and which are each connected to one pair of the series connected secondary windings 6. The upper ends of rotor contacts l4, l5 and I6 cooperate with circular rows of contacts 20, 2| and 22 that depend from insulated distributor block I I in which the same are preferably. moulded. Contacts 20, 2| and 22 terminate at the upper ends thereof in sockets formed in block I I and may be connected to spark plugs 3| by means of suitable radio-shielded cables that extend through openings in the top of easing cap la (Fig. 1). Although only a single set of conand 22 are seen in the drawings it is to be understood that similar sets, one for each cylinder of an engine, may be circumferentially disposed in distributor block II.

There is thus provided a novel ignition system embodying novel means tributing current therein which system is particularly adapted for use in multiple ignition engines. In the novel system provided each spark plug of each cylinder is connected in an individual circuit which includes a plurality of series connected coils and the coils for all of the circuits, the distributor and circuit breakers therefor are embodied in a single novelly constructed compact unit. The novel unit provided lends itself to fine and accurate timing adJustment of each individual spark in each cylinder and to the timing of the groups of sparks in each of several cylinders relative to the operation of the engine.

Although only a single embodiment of the invention has been illustrated and described in detail, it is to be expressly understood that the same is not limited thereto, for example, various changes may be made in the design and ar rangement of parts illustrated as will now be apparent to those skilled in the art without departing from the spirit and scope of the invention. For a definition of the limits of the invention, reference is had primarily to the appended claims.

What is claimed is:

1. Multiple ignition apparatus, characterized in that it has a plurality of ignition circuits, each coils in series connection, which, being arranged around a joint axis, are induced by the same magnet system, each of said coils including a primary and 'a secondary windmg.

2. In an ignition system, a plurality of ignition circuits, a plurality of series connected induction coils in each of said circuits, and a common magnetic rotor for simultaneously energizing the primary windings of all of said coils.

3. In an ignition system, a plurality of ignition circuits, each of said circuits including a pair of induction coils, the primary windings of each pair of coils being connected in series and the secondary windings of each pair of coils being connected in series, and common magnetic means for simultaneously energizing all of said primary windmgs.

4. In a multiple ignition system, a plurality of spark plugs, an individual circuit for supplying electric energy to each oi said plugs, each of said circuits including a. plurality of induction coils, the coils in each of said circuits having the prifor generating and dis mary windings thereof connected in series and the secondary windings thereof connected in series, and a single magnetic rotor for simultaneously energizing said coils.

5. In a multiple ignition system, a plurality of spark plugs, an individual circuit for supplying electrical energy to each of said plugs, each of said circuits including a plurality of induction coils, the primary windings in the coils in each circuit being connected in series and the secondary windings in the coils in each circuit being connected in series, means in each of said circuits for interrupting the flow of current through the primary winding thereof, and common magnetic means for simultaneously inducing current in all of said coils.

6. In a multiple ignition system for a multiple cylinder engine, a plurality of spark plugs in each cylinder, an individual circuit for supplying current to each spark plug in each cylinder, each of said circuits including a plurality of induction coils, the primary winding of the coils in each of said circuits being connected in series and the secondary windings of the coils in each of said circuits being connected in series, means in each circuit for interrupting the flow of current through the primary windings thereof, distributor means having a common rotating element for connecting the spark plugs of each cylinder in sequence in said circuits, and common magnetic means for simultaneously inducing current in said primary windings.

7. In apparatus of the class described, a casing, a rotatable shaft journaled in said casing, a magneto-generator in said casing comprising a magnetic rotor on said shaft and a plurality of induction coils symmetrically disposed about said shaft and having the axes thereof parallel to the axisof said shaft, stationary means for magnetically connecting the cores of said coils at one end, the other ends of said cores being positioned in air-gap inductive relation to said rotor, means for connecting the primary windings of each of several groups of said coils in series and for connecting the secondary windings of each of said groups of coils in series, a circuit interrupter in series with the primary windings of each of said groups, and distributor means for controlling the flow of high tension current from the secondary windings of said groups.

8. In apparatus of the class described, a casing, a rotatable shaft journaled in said casing, a

- magneto-generator having a rotor mounted on said shaft, a distributor including a distributor block having a recess in the outer face thereof and a rotatable element on said shaft between said block and said generator, and circuit breaker means mounted in part on said block in said recess, said last-named means including cam means onsaid shaft.

9. Multiple ignition apparatus with a permanent magnet system which is common to all cur rent circuits and with magnetic flux paths which are evenly distributed around the axis of the rotor, characterized in that the entire winding of each ignition circuit is arranged on at least two coils which are in series connection, each of said coils including a primary anda secondary winding, and a core for each of said coils disposed parallel to the axis of the rotor, said cores being arranged in cage-like fashion and magnetically joined by arcuate laminated bars.

10. Apparatus of the class described compriscasing, a magnetic rotor mounted on said shaft in said casing, a plurality of induction coils, means including a dielectric member for positioning said coils in said casing around the shaft, the cores of said coils being connected with each other at one end and in inductive relation with said rotor at the other end, circularly disposed conducting means on said member, means connecting said conducting means to the secondary winding of one of said coils-rotatable means on said shaft above said member, an insulated conductor carried by said rotatable means in close relation to said conducting means, a dielectric distributor block mounted in said casing above said rotatable means, said block having a recess in the outer face thereof around said shaft, a plurality of circularly disposed contacts on the lower face of said block positioned close to the path of said conductor, circuit breaker means mounted in said recess, and. means connecting said circuit breaker means in circuit with the primary winding of said one of said coils.

11. In apparatus of the class described, a casing, a rotatable shaft journalled in said casing, a magneto-generator in said casing having a rotor mounted on said shaft and at least one induction coil, an annular dielectric member in said casing, a distributor block cooperating with said member to form an annular chamber around. said shaft, a rotatable element on said shaft in said chamber, an insulated conductor carried by said element, conducting means mounted on said member and electrically connected to the secondary winding of said coil, and a plurality of circularly arranged terminals on said block, said conductor being adapted to conduct electrical current from said conducting means to said terminals in a predetermined sequence during rotation thereof.

12. In apparatus of the class described, a casing, a rotatable shaft journalled in said casing, a magneto-generator in said casing comprising a rotor mounted on said shaft and at least one induction coil, an annular dielectric member in said casing, a distributor block cooperating with said member to form a chamber around said shaft, a rotatable element on said shaft in said chamber, an insulated conductor carried by said element, conducting means mounted on said member and electrically connected to the secondary winding of said coil, a plurality of circularly arranged terminals on said block, said conductor being adapted to conduct electrical current from said conducting means to said terminals in a predetermined sequence during rotation of said element, and circuit breaker means for the primary winding of said coil mounted in a recess in the outer face of said distributor block, said last-named means including a cam on said shaft.

13. In apparatus of the class described, a casing, a rotatable shaft journalled in said casing, a magneto-generator in said casing comprising a magnetic rotor mounted on said shaft and a plurality of ignition coils disposed around said shaft and having the cores thereof parallel to the latter, a dielectric-partition member in said casing, a plurality of conducting means concentrically arranged on said member and electrically connected to the secondary windings of different ones of said coils, a distributor block cooperating with said member to form a chamber through which saidshaft extends, a rotatable element on said shaft in said chamber, a pluing a. casin a Shaft rotatably mounted in said rality of insulated conductors carried by said elementatdiflerentradialdistancestromtheaxis of said shalt for cooperation with said conducting means, and a plurality oi lets oi circularly arranged terminals on said block, each or said conductors being adapted to conduct electrical 6 current from one of said conducting means to the terminals of a diflerent one of said sets in a predetermined sequence.

14. In a magneto generator, a casing, a shaft Journalled in said casing, a magnetic rotor 'mounted on said shaft, a plurality of ignition 10 the secondary windings of each 01' said groups.

J AKOB BOHLI. 

